Im working wit the chtMultiRegion Solver.
After a couple changes buoyantBoussinesq I will add the radiation
in the Teqn. For a buoyant-Solver its easy with the guide "Radiation heat transfer in OpenFOAM" from chalmers http://www.tfd.chalmers.se/~hani/kur...Foam_final.pdf

Now im struggling with TEqn with radiation,
and I hope for little help or some clous about this topic.